Nov. 01, 2004
Donald Savage
Headquarters, Washington
(Phone: 202/358-1727)
Nancy Neal
Goddard Space Flight Center, Greenbelt, Md.
(Phone: 301/286-0039)
RELEASE: 04-360
NEW NASA SATELLITE TO STUDY BLACK HOLE BIRTH AND GAMMA RAY BURSTS
By the end of this day, somewhere in the visible universe a new black
hole will have formed. Gamma-ray bursts (GRBs), the most distant and
powerful explosions known, are likely the birth cries of these new
black holes.
NASA's Swift mission is dedicated to studying the gamma-ray
burst/black hole connection. The Swift spacecraft, an international
collaboration, is scheduled to lift off in November aboard a Delta II
rocket from Cape Canaveral Air Force Station, Fla.
"Swift caps off a 30-year hunt to understand the nature of gamma-ray
bursts, flashes of light that burn as brightly as a billion billion
suns," said Dr. Anne Kinney, Director of the Universe Division, NASA
Headquarters, Washington. "Swift is fine-tuned to quickly locate
these bursts and study them in several different wavelengths before
they disappear forever. Swift is a little satellite with a big
appetite," she said.
Gamma-ray bursts are fleeting events, lasting only a few milliseconds
to a few minutes, never to appear in the same spot again. They occur
from our vantage point about once a day. Some bursts appear to be
from massive star explosions that form black holes.
The Swift observatory comprises three telescopes, which work in tandem
to provide rapid identification and multi-wavelength follow-up of
GRBs and their afterglows. Within 20 to 75 seconds of a detected GRB,
the observatory will rotate autonomously, so the onboard X-ray and
optical telescopes can view the burst. The afterglows will be
monitored over their durations, and the data will be rapidly released
to the public.
The afterglow phenomenon follows the initial gamma-ray flash in most
bursts. It can linger in X-ray light, optical light and radio waves
for hours to weeks, providing great detail. The crucial link here,
however, is having a precise location to direct other telescopes.
Swift is the first satellite to provide this capability with both
great precision and speed. "We expect to detect and analyze over 100
gamma-ray bursts a year," said Dr. Neil Gehrels, Swift's Principal
Investigator at NASA's Goddard Space Flight Center (GSFC) in
Greenbelt, Md. "Swift will lead to a windfall of discovery on these
most powerful explosions in the universe."
While the link between some bursts and massive star explosions appears
firm, other bursts may signal the merger of neutron stars or black
holes orbiting each other in exotic binary star systems. Swift will
determine whether there are different classes of gamma-ray bursts
associated with a particular origin scenario. Swift will be fast
enough to identify afterglows from short bursts, if they exist.
Afterglows have only been seen for bursts lasting longer than two
seconds.
"Some bursts likely originate from the farthest reaches, and hence
earliest epoch, of the universe," said Swift Mission Director John
Nousek. He is a professor of astronomy and astrophysics at Penn
State's University Park, Pa., campus. "They act like beacons shining
through everything along their paths, including the gas between and
within galaxies along the line of sight," he said.
Swift notifies the community, which includes museums, general public,
and scientists at world-class observatories, via the GSFC-maintained
Gamma-ray Burst Coordinates Network (GCN). A network of dedicated
ground-based robotic telescopes distributed around the world awaits
Swift-GCN alerts. The Swift Mission Operations Center, located at
Penn State's University Park campus, controls the Swift observatory
and provides continuous burst information.
Swift, a medium-class explorer mission, is managed by GSFC. Swift is a
NASA mission with participation of the Italian Space Agency and the
Particle Physics and Astronomy Research Council in the United
Kingdom. It was built in collaboration with national laboratories,
universities and international partners, including Penn State
University; Los Alamos National Laboratory in New Mexico; Sonoma
State University, Rohnert Park, Calif.; Mullard Space Science
Laboratory in Dorking, Surrey, England; the University of Leicester,
England and the Brera Observatory in Milan, Italy.
More information about Swift is available on the Internet at:
http://swift.gsfc.nasa.gov
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